1. Field of the Invention
The invention relates to a system for opening and closing a flap for a motor vehicle mounted along one of its edge areas to a stationary structural component so as to be swivelable around a horizontal swiveling axis. The flap is driven by a first drive device and a second drive device acting in concert so as to be movable from a closed position into an open position, wherein the first drive device is an electromechanical drive device and the second drive device is a hydraulic, pneumatic, or hydropneumatic drive device.
2. Description of the Related Art
Opening and closing systems for vehicle flaps are known for opening and closing flaps such as hatchbacks, trunk lids, engine hoods, doors, and the like in motor vehicles. Often, both sides of the flap are driven electromechanically so as to prevent warping of the flaps when the flaps are open and closed.
Some drive systems are used that drive the flaps electromechanically on only one side, while a gas spring is arranged at the other side of the flap. The gas spring counterbalances the weight of the flap by substantially supporting only the opening of the flap. An opening and closing system of this kind is generally better than the variant that is driven electromechanically on both sides and is therefore preferred for installation in most applications.
In systems that are driven electromechanically on one side it is disadvantageous that the electromechanical drives are outfitted with pressure springs, typically embodied as helical pressure springs, which must counterbalance the weight of the flap so that the motor has reasonable dimensions in terms of the vehicle construction and the flap can be safely held in a partially closed position or in the completely open position.
Further, it is disadvantageous with respect to installation space when the flap is stopped in desired positions by other braking elements or clamping elements.